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101.
School violence and vandalism are at crisis level. The investigators attempted to employ strategies that would attack identified procreators of school violence and vandalism existing within our schools. The effects of these strategies on vandalism costs, student attendance, off-task and disruptive behaviors, and on various kinds of positive teacher-student contacts were investigated in 19 elementary schools. Results indicated that the dollar costs of vandalism and frequency of inappropriate student behaviors decreased more in experimental than in control schools. Student attending and positive teacher-student contacts improved, or remained higher, in the experimental than in the control schools.  相似文献   
102.
Recovery from adaptation to NaCl was tested by comparing some relevant parameters of response to the adapting and test stimuli separated by different recovery intervals. The time course of response was determined using magnitude estimations and using the flow chamber for stimulus delivery. The course of recovery for all parameters used was a negatively accelerated function of the rest time, but the recovery rate of different parameters did not prove to be equal. Recovery was fastest for the initial maximum taste magnitude, followed by the time needed for the taste to disappear. The taste effect summed over time and the time required for the taste magnitude to decrease to 30% of its preadapted maximum were the slowest to recover. Although the recovery processes proceeded at a rapid rate during the initial period, all parameters remained depressed over a rather long period.  相似文献   
103.
Recovery from adaptation to NaCl was tested by comparing some relevant parameters of response to the adapting and test stimuli separated by different recovery intervals. The time course of response was determined using magnitude estimations and using the flow chamber for stimulus delivery. The course of recovery for all parameters used was a negatively accelerated function of the rest time, but the recovery rate of different parameters did not prove to be equal. Recovery was fastest for the initial maximum taste magnitude, followed by the time needed for the taste to disappear. The taste effect summed over time and the time required for the taste magnitude to decrease to 30% of its preadapted maximum were the slowest to recover. Although the recovery process proceeded at a rapid rate during the initial period, all parameters remained depressed over a rather long period.  相似文献   
104.
Aggression among female rats is almost entirely confined to the period of late pregnancy and lactation. Behaviorally it is similar to the aggression of males including piloerection and lateral attacks, but it differs in its function. Unlike male aggression which serves to establish a social hierarchy and a territory, i. e., is competitive, maternal aggression is protective, i. e., it serves to prevent predation of the mother's offspring. In this respect it is closely related temporally and causally to maternal care; if the offspring are removed maternal aggression wanes almost immediately–its function no longer exists! Studies on aggression by mothers, among rats, from the author's laboratory are reviewed and comparisons made with maternal care. As noted, maternal aggression and maternal care are closely related during the cycle of maternal behavior and they share a similar hormonal basis and possibly the effect of uterine stimulation, but maternal care requires prolactin and the decline of progesterone while maternal aggression appears independent of pituitary hormones and does not require a decline in progesterone. Maternal aggression like maternal care appears to be organized into a hormonal phase, during pregnancy, parturition, and for about a week postpartum and a nonhormonal phase thereafter. Bilateral radiofrequency lesions of the lateral midbrain peripeduncular nucleus (PPN) produce deficits in maternal aggression if made on lactation day 7 (L7), but not earlier, without producing significant deficits in maternal behavior. Experiments showed that the PPN does not mediate hormonally stimulated maternal aggression; it appears to mediate only nonhormonally stimulated maternal aggression. Studies on the role of pregnancy hormones on long-term retention of maternal aggression and the role of olfaction in maternal aggression are also reviewed. © 1994 Wiley-Liss, Inc.  相似文献   
105.
The authors examined whether differences between children and adults in the application of muscle forces during a dynamic-contact task (cycling) can be attributed to children's relatively lower segmental mass and moment of inertia. They examined pedal-force construction as adults and younger and older children (n = 7 in each group), with and without mass added to their limbs, pedaled an appropriately scaled bicycle ergometer. When mass was added to their limbs, children adjusted muscular forces on the pedal in a way that began to approach the pattern demonstrated by adults. Because age, neuromotor maturation, and motor experience were held constant, it seems plausible that by 6 to 8 years of age, and perhaps younger, physical size and growth limit children's production of adult-like muscle forces on the pedal.  相似文献   
106.
Paradis (1992) likens studies of bilingual laterality to reported sightings of the Loch Ness Monster, in that although some studies claim differential laterality much conflicting research evidence does not-and like the mythical Scottish monster, what reason have we to suspect that any such phenomenon might exist? This study reexamines differential bilingual laterality using four groups of English-Welsh bilinguals which differ in their age of acquisition and in their environment of acquisition. Using a split visual field paradigm we present evidence which, supports the notion of greater right hemisphere processing in a later learned language. Our findings also suggest the pattern of lateralization in bilinguals is strongly affected by the specific language environment during development such that the shift toward greater right hemisphere involvement for the later learned language will be more pronounced in individuals which are brought up in areas where that language is not regularly heard.  相似文献   
107.
The early evolution of Jean Piaget's clinical method   总被引:1,自引:0,他引:1  
This article analyzes the early evolution of Jean Piaget's renowned "clinical method" in order to investigate the method's strikingly original and generative character. Throughout his 1st decade in the field, Piaget frequently discussed and justified the many different approaches to data collection he used. Analysis of his methodological progression during this period reveals that Piaget's determination to access the genuine convictions of children eventually led him to combine 3 distinct traditions in which he had been trained-naturalistic observation, psychometrics, and the psychiatric clinical examination. It was in this amalgam, first evident in his 4th text, that Piaget discovered the clinical dynamic that would drive the classic experiments for which he is most well known.  相似文献   
108.
Advances in the medical treatment of HIV have made it clear that adherence to highly active antiretroviral treatment is a crucial feature for treatment success. The present paper had two goals: (1) to examine psychosocial predictors of adherence in persons receiving HIV antiretroviral therapy; (2) to compared two minimal-treatment interventions to increase HIV medication adherence in a subset of persons who self-reported less than perfect adherence. One of the interventions, Life-Steps, is a single-session intervention utilizing cognitive-behavioral, motivational interviewing, and problem-solving techniques. The other intervention, self-monitoring, utilizes a pill-diary and an adherence questionnaire alone. Significant correlates of adherence included depression, social support, adherence self-efficacy, and punishment beliefs about HIV. Depression was a significant unique predictor of adherence over and above the other variables. Both interventions yielded improvement in adherence from baseline, and the Life-Steps intervention showed faster improvements in adherence for persons with extant adherence problems.  相似文献   
109.
In this paper we study proof procedures for some variants of first-order modal logics, where domains may be either cumulative or freely varying and terms may be either rigid or non-rigid, local or non-local. We define both ground and free variable tableau methods, parametric with respect to the variants of the considered logics. The treatment of each variant is equally simple and is based on the annotation of functional symbols by natural numbers, conveying some semantical information on the worlds where they are meant to be interpreted.This paper is an extended version of a previous work where full proofs were not included. Proofs are in some points rather tricky and may help in understanding the reasons for some details in basic definitions.  相似文献   
110.
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